[jasons_98gt]

car must of been burning oil for some time now as i did not want to suspect!
it was only doing it in the morning, some gray smoke, and sometimes none at all.

I was driving it over the weekend and now when i give it gas and rev it up to about 2 rpms i can see the smoke, checked the oil and it was about a quart low shit,
must be rings just to afraid to do a compression test to verify it.

has anyone ever reused the pistons in an overhaul? im guessing its not recommended, just afraid those are going to be expensive as hell! Not looking for anything fancy just a stock bottom end, not forged or anything.

Someone had a 4.6 shortblock for sale with a spun main for 150 bones.
Was thinking about getting that and rebuild that as i was still driving mine

[jasons_98gt]

ok so i done a compression test and added a few drops of oil and didnt see a increase.
according to the book it should increase if the rings are worn.

Any ideas? this thing is running like shit, barely pulling hills even up to 4000 rpms theres NO power a frigging 4 banger jeep even smoked me! Theres something definitely up.
Its still smoking once in a while...

[jasons_98gt]

compression was around 165 at all 8 cylinders

[BAD98GT]

i would do a vacume check, check your pcv valve(located on the valve cover.
could b anything from piston rings, valve stems or valve guides could be worn, valve seals. a vacume test can get you a general idea of where he problem lies

[Ryan Paymaster]

People jump on me a bit but these motors will start destroying oil and it's usually valve related. You could search my name and find my preaching this in 9000 posts. When my engine was torn down the builder said there were just a few issues with a few valves. When asked about the rings he said possibly but they looked okay in general. The big issue was the valves (and a faulty head but that wasn't the oil source as far as I know and what he said.)

I lost top end power due to oil consumption but I also have a Cobra. It would fog the street in pure blue smoke which is pretty clear. Just do the two tests and see what they results in. I wouldn't jump to too many rebuilding conclusions assuming it's just on startup. Could just need a real good tuneup?

[jasons_98gt]

im guessing bottom end here, for the simple fact i did the PI swap and the heads were bought brand new and have about 20 some thousand on them.

The bottom end however just turned 204,000. I checked the plugs like 2 weekends ago and they were all clean, just had to regap a few of them. The exhaust smells really rich though, maybe just because theres no cats probably.

But i used to have a camaro that i put new injectors in from napa one time and it ran like shit and got gray smoke like im getting from the stang and it turned out the injectors were junk. I put the old ones back in presto no more smoke lol.

But i will do a vacuum test sooner or later, but the motor seems pretty healthy no noises starts right up after 3 cranks, old gal is just getting old

[tfofkyle]

110k miles on my bottom end. started using oil like yours too. swapped to npi heads with a fresh valve job, pi cams, pi intake. no more oil consumption also about 165 psi for my compression test too.

[jasons_98gt]

yeah, wish i could say the same.
these heads are new still and i never beat the car.
Im getting good results wet and dry tests, plus are clean and firing.
Someone told me that when my old x pipe was leaking at the manifolds it could of been drawing cool air in and burned the valves
anyone hear of this?

[jasons_98gt]

found the problem!
did a fuel pressure test, turned the key to pump pressure up 15lbs, turned it off bleeds down real fast. So i started it shes putting about 12lbs out sheesh

swapped fuel regulators out to eliminate the problem and changed the fuel filter no change, looks like i need a fuel pump ladies and gents.

badipadip thats all folks!

[tfofkyle]

i think mines about to go as well. just made an exhaust vid and my fuel pump is whining hardcore.

[jasons_98gt]

yeah it might be,
im still unsure of why the car is smoking though, i doubt a fuel pump would cause that

[tfofkyle]

fwiw mine does smoke sometimes too. im thinking it may just be running a little rich ? id be afraid for you and me if it were blueish/white like mine was when i was gushing oil out of my valve stem seals. but grayish/black indicated a rich condition as far as i know. for the meantime, mines not clogging up the drivethru with a cloud of smoke lol and for that im happy.

[brharris777]

im having a relative problem with my 98 cobra. On starts after its been sitting for a while is makes one puff of smoke out of the passenger tailpipe. Im assuming it vavlve related but god i hope not. I haz no moniez for valve work.

[jasons_98gt]

man my shit must have a gremlin or something in it!
car is running a-1 and i didnt even do anything to it. I haven't seen anymore smoke for the past 2 days the fuel pressure is back to 40lbs at idle its holding for 10 minutes after shut-off.
Probably passed a piece of dirt or something out of a fuel line somewhere.

[tfofkyle]

makes me feel better. mines still a lil smoky too, hope its just some dirt and stuff from my swap as well.

[zigbigadoru]

from what i understand valves shouldnt really have anything to do with oil consumption. usually if compression is down and oil is being consumed it is either the rings or the head gasket. now im not saying that it ISNT the valves but oil+valves just doesnt sound right, ya know?

the reason i say that is because i have a ford aspire that really doesnt use oil and has low compression in 2 adjacent cylinders. now that usually points at a head gasket, however it just guarantee it. i washed my engine and made sure there was no oil anywhere on the engine so if the gasket was leaking i would be able to spot the oil real easily. i eliminated piston rings because it wasnt burning oil, the oil was nice and clean, and it was smoking blue out the exhaust. about a week or so ago i spotted oil out of the valve covers so i determined it was the head gasket that was bad. now when i go to take it apart im still going to inspect the valves and put some regrinding paste on them so the seal between the valve and the seat is good but i pretty much know that im going to find that they are good.

[jasons_98gt]

yeah, i know with valves the oil can either get past the seals, or if the stems are worn, it can also sneak past there.

Im going to go for a piece of mind since its staring to warm up here switch back to 10w-30 even though theres not much of a difference.

someone told me to use 15-30 or 20-50 haha i was like F that.
asking for trouble there...

[tfofkyle]

zig, its common on the early 4.6's, 95-96 as far as i know, around 100k miles, especially in crown vic's and other panther platforms for the guides and seals to wear down prematurely, causing some blow-by. pay attention when you see those older panther platforms take off from the lights - theyll all have that light blueish smoke, some are pretty bad. ford fixed the problem in 97 i believe. if youd like to go through and research all the npi casting numbers they can tell you what models are bad and such.

my cylinders all checked out 165 across all cylinders, barely even 1-2 psi difference between any two, and the cylinders held the compression for a long time. i too suspect maybe a head gasket problem, but my heads are freshly decked, and i used ford racing gaskets, everything was clean and installed correctly, so who knows.

[zigbigadoru]

is the valve just not sealing on the seat properly or do the seats like fully wear down?

[Blower Head]

What causes the oil consumption is the wear of the valve seals and in more extreme cases the valve guides get worn. I was using a little oil (1 quart in 3k miles) at about 80k miles. When I changed my cams and valve springs I put new valve seals in and that took care of it.